Third Person Camera Collision

[Arkane]

Hi,

 

I'm testing Thid Person Camera. I have searched for tutorial on the forum .

My camera is based on Aggror tutorial but I don't know how to handle camera collision to avoid seeing through walls.

 

I know there are differents solutions to handle that (camera sphere, raycast, ...) :

 

http://www.gamasutra.com/blogs/EricUndersander/20131001/201382/Accurate_Collision_Zoom_for_Cameras.php

 

or

 

http://books.google.fr/books?id=az_Oi9mSSiIC&pg=PA681&lpg=PA681&dq=third+person+camera+collision+sphere&source=bl&ots=CDTY7nJpfL&sig=sDnRf4DgJkJg39vSmNwI8vJlQ2U&hl=fr&sa=X&ei=gxAOVMOrAY2Xar_tgNAF&ved=0CCoQ6AEwATgK#v=onepage&q=third%20person%20camera%20collision%20sphere&f=false

 

What's the best method ?

 

Can someone help me posting code to show me how to handle that problem ?

 

Thanks !

[cassius]

Its the player that collides not the camera.Agggror creates a pivot for the player. This is what collides with stuff. I am referring to the Aggror c++ tutorial.

[cassius]

If you meant how to avoid camera becoming unsighted behind walls then raycasting is one answer and Aggrors c++ tutorial has an example.

[tjheldna]

Here is a snippet from my third person camera code, pretty sure I derived it from Aggrors Tut (can't remember). Obviously a lot of the variables are declared somewhere else the section you are after is the Pick. Note you need to set the characters pick mode to 0 else the pick will hit the model and wont work.

 

GetCameraTarget() returns an entity that the camera is tracking

 

Let me know if you have any questions

 

void ChaseCamera::Update(void)
{
BaseCamera::Update();
if (GetCameraTarget())
{
Vec3 lastPosition;
Vec3 lastRotation;
BaseObject* object = (BaseObject*)GetCameraTarget()->GetUserData();
//Calculate the furthest TPS pivot position
tpsPivot->SetPosition(GetCameraTarget()->GetPosition());
Vec3 pickPos = GetCameraTarget()->GetPosition();
pickPos.y += GetHeight();
Vec3 rot = tpsPivot->GetRotation();
Vec3 pos = tpsPivot->GetPosition();
pos.y += GetHeight();
tpsPivot->SetPosition(pos);
rot.y = -characterYaw;
rot.x = -characterPitch;
tpsPivot->SetRotation(rot);
entity->Point(tpsPivot);
tpsPivot->Move(0.0, GetHeight(), -GetCamDistance(), false);
//Use a pick to determine where the camera should be
PickInfo pick;
GetCameraTarget()->SetPickMode(0);
if (World::GetCurrent()->Pick(pickPos, tpsPivot->GetPosition(), pick, 0.0F, true)) tpsPivot->SetPosition(pick.position);
GetCameraTarget()->SetPickMode(Entity::SpherePick);
//Apply position
lastPosition.x = Math::Curve(tpsPivot->GetPosition().x, entity->GetPosition().x, (GetSmoothness()) / Time::GetSpeed());
lastPosition.y = Math::Curve(tpsPivot->GetPosition().y, entity->GetPosition().y, (GetSmoothness()) / Time::GetSpeed());
lastPosition.z = Math::Curve(tpsPivot->GetPosition().z, entity->GetPosition().z, (GetSmoothness()) / Time::GetSpeed());
entity->SetPosition(lastPosition);
}
}

[Arkane]

Thank your for your answers. I will try to implement similar thing in my TPS camera code (when I'll be back home after work).

 

I'll let you know if it works ;-).

[Arkane]

So I found a workaround to handle my camera and not see through walls when I'm in a house for example.

I've changed the pick radius and it works. After I will try to improve my camera rotation around the player.

 

Based on Aggrors tutorial :

 

//Update camera position
Vec3 playerPosition = player->GetPosition();
Vec3 cameraPosition = fpsPivot->GetPosition();
float cameraHeight = crouching ? crouchHeight : playerHeight;
cameraPosition.y = Math::Curve(playerPosition.y + cameraHeight, cameraPosition.y, cameraSmoothing);
cameraPosition = Vec3(playerPosition.x, cameraPosition.y, playerPosition.z);
fpsPivot->SetPosition(cameraPosition);

//Position and rotation of FPS camera
camera->SetPosition(fpsPivot->GetPosition());

//Postion and rotation of TPS camera
tpsPivot->SetPosition(fpsPivot->GetPosition());
tpsPivot->Move(0, 1, maxCameraOffset);

//Checking if Space key is pressed
if (window->KeyHit(Key::Space))
{
isFpsCam = !isFpsCam;
}

// Checking camera mode
if (isFpsCam)
{
camera->SetPosition(fpsPivot->GetPosition());
camera->SetRotation(fpsPivot->GetRotation());
}
else
{
camera->SetRotation(fpsPivot->GetRotation());
camera->SetPosition(tpsPivot->GetPosition());
}

//Raycast to check TPS Camera obstacle
PickInfo pick;
if (world->Pick(fpsPivot->GetPosition(), tpsPivot->GetPosition(), pick, 0.5, true) && !isFpsCam)
{
camera->SetPosition(pick.position);
}

 

You can adjust pick radius a bit to have a better behaviour.

[cassius]

Well done arkane. Good luck.

[Arkane]

I've found a good tutorial about TP camera collision/occlusion. It's for Unity but I think we can make the same in leadwerks.

 

http://www.3dbuzz.com/training/view/3rd-person-character-system/enhanced-character-system/11-occlusion-and-collision-overview

 

There is more videos about third person camera here :

 

http://www.3dbuzz.com/training/view/3rd-person-character-system/enhanced-character-system

 

Can someone tell me if it is possible to port it to leadwerks ?

 

Thanks!

[Arkane]

I saw in camera.h that there is localfrustumpoints and frustumpoints. What is the difference ? What if the order of each point in those arrays ?

Can I use them to get the near camera plane and the far camera plane of the view frustrum ?

 

Maybe is it easier to use Camera::GetRange() and Camera::GetFOV () then calculate the four points of the near camera plane ?